Why didn't the kids' deceased mom show up in the movie towards the end? That would've been nice if she could've interacted with the older daughter or something.
shareShe wasn't descended from the same family as the rest of them were. Unless you're making some sort of sick joke about how you believe that Bill Cosby married his sister. That's disgusting of you.
shareTechnically, Elliot did not die, his spirit just was ejected from his body after the accident. The ability to stay out of the body, as a "ghost" only lasts a few days, which is why he was starting to fade in/out near the end. If his spirit had not reunited with his body, hist spirit would have passed on to the afterlife.
Since the mother had actually died, and been dead for some time, she could not come back as a ghost within the story line.
In addition, the ability for a spirit to be scared out of the body when the body was not actually dead, was a hereditary thing, passed on in Elliot's bloodline,